126210421 has 2 divisors, whose sum is σ = 126210422. Its totient is φ = 126210420.

The previous prime is 126210419. The next prime is 126210439. The reversal of 126210421 is 124012621.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 124211025 + 1999396 = 11145^2 + 1414^2 .

It is a cyclic number.

It is not a de Polignac number, because 126210421 - 2¹ = 126210419 is a prime.

Together with 126210419, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (126210451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 63105210 + 63105211.

It is an arithmetic number, because the mean of its divisors is an integer number (63105211).

Almost surely, 2^126210421 is an apocalyptic number.

It is an amenable number.

126210421 is a deficient number, since it is larger than the sum of its proper divisors (1).

126210421 is an equidigital number, since it uses as much as digits as its factorization.

126210421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 192, while the sum is 19.

The square root of 126210421 is about 11234.3411466806. The cubic root of 126210421 is about 501.6087131993.

The spelling of 126210421 in words is "one hundred twenty-six million, two hundred ten thousand, four hundred twenty-one".